The Importance of Order in Blood Draws

The order your blood is drawn can completely wreck your lab results. It’s not random. Phlebotomists follow

a strict “Order of Draw,” and there’s a secret mnemonic: “You Like Really Good Looking Guys.”

Yellow for cultures, Light Blue for clotting, Red, Green, Lavender,

then Gray for glucose. Get the order wrong, and additives from one tube can contaminate the next,

messing everything up. Also, that tourniquet can't stay on for

more than 60 seconds, or your red blood cells can literally explode—a process called hemolysis.

And we never shake the tubes, just gently invert them. It's all about the

details.